The atmosphere grew tense at the makeshift camp as migrants, who had been relying on aid agencies to distribute food and water, were drenched by an overnight rainstorm.

Macedonia was forced to close its border, after the influx of migrants grew to 2,000 a day, after nearly 40,000 illegally entered the country last month. The country then attempted to control the inflow, reinforcing the border, and handing out transit visas to just several hundred people each day, despite several massed attempts to break through from predominantly young male migrants.

The vast majority of the incomers dodge a fare to immediately board a train destined for Serbia in the north. From there they enter Hungary, an EU state in the borderless Schengen zone, and travel further north, primarily to Germany, Scandinavia and France.

Hungary is currently constructing a fence on its Serbian border, incentivizing thousands of travelers to make the journey from Greece now, before it is completed. According to the UN, more than 170,000 refugees and migrants have arrived in Greece by sea this year, far in excess of last year’s numbers.

On Saturday alone, the Italian navy rescued 1,700 migrants in the Mediterranean, after receiving distress calls from two dozens ships.